Truckdoug's HD-Z 4L80e upgrade kit
Intended to solve the problems I see most units have. This kit is meant for a performance vehicle with a higher than stock stall speed converter. You can still use this kit for a low (<2500rpm) stall converter but I recommend using the stock separator plate to keep the 1st to 2nd gear accumulator and plugging the case the traditional way via the included .388" cup plug
Intended to solve the problems I see most units have. This kit is meant for a performance vehicle with a higher than stock stall speed converter. You can still use this kit for a low (<2500rpm) stall converter but I recommend using the stock separator plate to keep the 1st to 2nd gear accumulator and plugging the case the traditional way via the included .388" cup plug
Intended to solve the problems I see most units have. This kit is meant for a performance vehicle with a higher than stock stall speed converter. You can still use this kit for a low (<2500rpm) stall converter but I recommend using the stock separator plate to keep the 1st to 2nd gear accumulator and plugging the case the traditional way via the included .388" cup plug
Truckdougs’ HD-Z 4L80e upgrade kit Includes:
Pump wear shield to help keep pump stator halves alive with high line pressure and RPM
HD separator plate eliminates the entire accumulator valve train. It also eliminates the need for plugging the case for dual feed mod.
3/4 accumulator block off. With the HD plate it essentially replaces the 3-4 accumulator housing. With a stock VB separator plate you can keep the 1-2 accumulator and delete only the 3&4 accumulators with this plate.(in that case you would need to plug the case) Hardware is included. 120in/lbs
HD direct springs are added to prevent centrifugal apply of the direct clutch (a .060” bleed hole is still required)
New, stock-dimension boost valve and PR bore o-ring plug. Much of the problems I see folks have are related to worn boost valves. I prefer this version over the LB1. The o-ringed bore plug eliminates the common leaky bore plug known to cause high line pressure issues.
195psi pressure regulator spring. This is a boost from the stock 170-ish. Along with the new boost valve you will see 190-200 psi in a good pump and thats enough for 1000 hp depending on your clutch stacks and clearances. My preference is Green Borg HE frictions, plain non-turbulator steels with the clutch clearance on the very tight side of factory spec. .010” per friction is a good starting place.
Output shaft to case bushing. Retain with green locktite and leave the grooved edge proud into the case about .050” to give the roller bearing a place to locate.
Output shaft torrington bearing. Reduce drag and wear. The side with the ID lip should be located by the output shaft bushing. Installing the wrong way will eat the bearing up and send a bunch of debris into your new transmission. Remember: ID LIP SIDE AGAINST THE CASE
Shims for previous bearing to set rear end play. Usually one .010 shim gets you to the ideal .005 to .012 rear play. Always check! This is one of those things that sets a BUILT transmission apart from “refreshed” unit. Whatever your rear end play number is, make sure your front endplay is atleast double. A good result would be .010 rear and .020 front. Use front pump selective shims to set front endplay.(
HD intermediate clutch spring retainer plate. Rid yourself of the flimsy stamped one.
HD intermediate snap ring. This holds the intermediate pressure plate in place much better that the stock piece which is also commonly found broken.
Consider adding the sonnax case saver (pn34762-10 ‘91-’98, pn34762-20 ‘99+), they do help prevent hot spots on your second gear clutches from the pressure plate flexing.
If you have questions you are welcome to email me littlevictoryfabco@gmail.com
Thank you for choosing my parts for your ride. This is the stuff that goes into my cars and the units that I build for a living.